Darkwitch Rising was an absolute bitch to write, but a wonder to research, and I'm very, very happy with the result ... although, frankly, it could have been two books, there's so much in it ...

One of the best things for me personally about Darkwitch Rising is that I was able to set it in one of my favourite places on earth, in the mysterious Idol Lane in London, but that also I was handed a massive surprise right at the end of writing. My editor at HarperCollins, Stephanie Smith, asked me to shift some of the scenes of action from the Faerie where they took place to a real and tangible place in London - so I chose the Tower of London (the place needed to be labyrinthine, and the Tower complex worked nicely, as well as being very close to Idol Lane). Working frantically against a tight deadline I did some quick research in the Public Record Office at London trying to discover the names of someone who worked in the Tower at the date I needed ... and to my absolute stunned amazement discovered that one of the Gentlemen of the Tower at that time was a certain Frederick Warneke ... one of my German ancestors. And on the right side of the bars for once! So I have one of my ancestors in the book, a wonderful thrill, and I gave him Ariadne to keep him happy.

Darkwitch Rising is set during one of the most turbulent times in English history, the period between 1629-1666 which encompassed civil war, Oliver Cromwell's Commonwealth, the magnificent restoration of Charles II, and the terrible events of the early to mid-1660s, encompassing both plague and the terrible Great Fire of London.

Ariadne is back, determined to take her place in the Game at last. She's a nice malevolent surprise popping up mid-book.

Cornelia-Caela is back as Noah Banks, just an ordinary woman, but one distantly related to Anne Russell, Countess of Bedford. Noah begins life as the countess' companion at Woburn Abbey, but all too soon Asterion reaches out to snatch her (remember that at the end of God's Concubine I revealed that Caela had one of Asterion's terrible imps within her) and drags her into his strange, strange world of Idol Lane.

Asterion is clearly identifiable this book - he's Weyland Orr, a brothel keeper (isn't he always the charming sort?) running a nasty little house of ill repute smack bang next to the church of St Dunstan's-in-the-East in Idol Lane. His chief whore is none other than his younger sister, Jane, and she is none other than Genvissa-Swanne reborn, now sunk as low as it is possible to go. Jane gets rehabilitated in this book, although she continues to annoy with her sharp tongue.

So, what happens ...

As if I'm going to tell you! But I will give you some hints. The Stag God rises in this book - I'm sure most of you know who he will be, but be prepared for just a little surprise! - but so does another mythical creature, the Green Man, who I call the Lord of the Faerie. Ariadne returns, determined to get her way, and carrying a couple of nasty little secrets that will blow the story line wide open. Weyland Orr has a couple of surprises himself, the least of which is what he has built on the top floor of his house on Idol Lane. Brutus and Coel return, as do all of Eaving's Sisters, but they spend much of their time in exile.

Read an extract.